A high-risk pregnancy may endanger the health and lives of the mother or baby. Which conditions cause high-risk pregnancies and what can you do to ensure a healthy pregnancy and baby?

Our specialists at the Department of Obstetrics & GynaecologySingapore General Hospital​, a member​ of the SingHealth​ group, reply your questions about high-risk pregnancy.

Question by sl190994

​Hi Doc, I am 28 weeks pregnant and have high BP. I was diagnosed with a condition called pre-eclampsia and I’m concerned my baby may be delivered early.

I am very very worried. Any advice on what I can do to deal with this condition? Thank you in advance.

Answered by the Department of Obstetric​​s & Gynaecology​​​​:

Dear sl190994,

Pre-eclampsia is a special kind of hypertension (high blood pressure) that develops in pregnancy. The diagnosis is made when a pregnant mother is noted to have high blood pressure (typically after 20 weeks). When her urine is tested, an increased amount of protein is noted. Risk factors for pre-eclampsia include being a first time mother, conceiving at an older age, pre-eclampsia during a previous pregnancy, being obese, carrying twins and being diabetic.

Pre-eclampsia can affect multiple organ systems in the body, especially the kidneys and the liver. The high blood pressure, if uncontrolled, may trigger fits in the mother putting both mother and baby at danger. The cause of pre-eclampsia is thought to be related to improper formation and functioning of the placenta. When pre-eclampsia develops earlier in a pregnant mother (especially before and around 28 weeks), the baby’s growth may be affected resulting in a small or growth-restricted baby. The affected mother’s blood pressure can be controlled with medications but once pre-eclampsia develops, the only cure is to deliver the baby.

While the decision to deliver a baby when pre-eclampsia develops at term (above 37 weeks) is straightforward, a similar decision when the baby is premature can pose a serious dilemma. Ultimately, a balance needs to be struck by your doctor, taking account into how safe it is to continue with the pregnancy (looking into how well-controlled the mother’s blood pressure and how healthy the unborn baby is), versus making the decision to deliver the baby prematurely especially if both the mother and baby are unwell.

There is a higher risk for pre-eclampsia to develop again in the mother’s next pregnancy. In these mothers, a medication called aspirin can be given to lower the risk of pre-eclampsia. There is good evidence that aspirin is useful for these mothers, particularly if it is given before 16 weeks’ gestation. Calcium supplements in women who may be calcium-deficient have been suggested to reduce the possibility of pre-eclampsia from developing. However, neither aspirin nor calcium can treat pre-eclampsia once the condition has developed.

Question by gemini29

Hi Dr, I am 20 weeks pregnant and I was told that I have Gestational Diabetes..this is my 3rd pregnancy and the first time for GD. I tested my glucose levels this morning and my readings are: 8.0, 8.7 and 9. I’m curious to know that if I start on a healthier diet today, will my glucose readings go down immediately or does it take a few hours for it to stabilise? Thank you.​

Answered by the Department of Obstetric​​s & Gynaecology​​​​:

Dear gemini29,

Gestational diabetes mellitus (GDM) is a special kind of diabetes that develop during pregnancy in mothers who were previously not diabetic. GDM, if poorly controlled, can lead to adverse pregnancy outcomes including very large babies that may make delivery dangerous and risky to both mother and baby. At the same, mothers with GDM are at higher risk of experiencing stillbirths (losing the life of the unborn baby unexpectedly) especially in cases of poor control. It is important that for a mother who experience GDM to undergo repeat testing 1.5-2 months after her baby has been delivered, to ensure that the diabetes resolves. The majority of GDM mothers would expect to be no longer diabetic by then, but it will be important for them to adopt healthy lifestyles that include watching their weight, exercising regularly and eating healthily as they are at risk of developing diabetes in later life.

It is not completely clear from your post whether the readings were from an oral glucose tolerance test (which is performed by a doctor and involves taking blood after an overnight fast, followed by blood tests performed within two hours after drinking a sugar drink prepared in the clinic) or from home finger-prick testing. Assuming that these were from an oral glucose tolerance test, the results would confirm that you have gestational diabetes (the normal readings are less than 5.1 at fasting, and less than 10 at one hour and less than 8.5 at two hours after consuming the sugar drink). If the readings you have quoted are from home finger-prick testing, these values would be considered high regardless if the tests were performed before your meals or at two hours after meals.

The first-line treatment for gestational diabetes is with diet-control. The aim of diet-control is to prevent sudden fluctuations in your blood sugar levels which can affect the growth and health of your unborn baby. Depending on your doctor, he or she may arrange for you to meet a dietician who can advise you on the modifications that can be made to your diet so as to prevent severe blood sugar fluctuations. In Singapore practice, the common targets a pregnant mother with GDM should achieve are for a blood sugar level of 4.4 to 5.5 before meals, and a level of 5.5 to 6.6 two hours after the start of a meal. Most mothers with GDM on diet-control would be advised to monitor their blood sugars via finger-prick testing at least one day in a week. During that particular day, the mother would be required to do finger-prick tests seven times throughout the day: three times before breakfast, lunch and dinner, another three times two hours after starting breakfast, lunch and dinner, and one final time at bedtime. If the readings are on target, the mother can continue on diet-control during delivery.

The majority of mothers with GDM would expect to see an immediate improvement in their sugar readings once dietary modifications are made. Lifestyle modifications such as adopting regular exercise or even going for a walk after a meal may also be helpful. Some mothers may find the blood sugar control increasingly challenging as their pregnancies advance due to the increasing hormones in pregnancy which tend to raise blood sugars. In these mothers, medications (in the form of tablets or injections) may need to be prescribed. Depending on how well the blood sugar is controlled, your doctor may advise for your baby to be delivered, usually via an induction of labour if feasible, between 38-40 weeks to minimise the risk of a stillbirth. Even though the delivery is before the estimated delivery date, these babies are considered mature (at term) and are at low risk for problems that premature babies may experience.

Question by catbear

Dear Dr, my husband (aged 31) and I (aged 36) have been trying for a child for close to 3 years now. I have a suboptimal tube, 2 uterine fibroids, 2 ovarian cysts and endometriosis near my intestine. I can't afford laparoscopy so we tried 2x hcg jabs, 4x clomid, 2x letrozole and had 2 unsuccessful IUIs. We were advised to do IVF asap I still have a good egg reserve. But I have some concerns.

1) My sisters in law both have had to terminate pregnancies because their babies were not well.

2) My husband's late sister had robin pierre syndrome and diamond blackfan anemia.

What's the likelihood that we may face the same challenges and are there any tests we can do to lower our risk?​

Is IVF a good option, and will i be able to have a healthy pregnancy, in light of these concerns? We both don't have high BP, cholesterol or diabetes.

Answered by the Department of Obstetric​​s & Gynaecology​​​​:

Dear catbear,

With regards to the points you raised:

1) You will need to provide more details about the circumstances during which your sisters in-law had to terminate their pregnancies including the reasons why their babies were determined to be “not well”.

2) Pierre Robin Syndrome (PRS) is a condition that develops before the baby is born in which there are three main features: cleft palate, abnormal positioning of the jaw and jawbone (small chin), and a retraction of the tongue. Most cases are sporadic (happen randomly), although there have been cases that have been reported to run in families. The most important medical problems faced by PRS babies are difficulties in breathing and feeding although most PRS babies do grow to lead a healthy and normal adult life. 

Diamond-Blackfan anaemia (DBA) is a form of anaemia that develops usually right after birth. About 10-25% of affected individuals have a family history of the disease. There may also be malformations involving the face (e.g., cleft palate), the upper limbs and the heart in up to half of affected individuals. DBA patients are at risk of developing leukaemia and other cancers.

It is important to establish if your husband or any of his family members have any of the stated problems. The best way is to seek an opinion from a geneticist. In most cases, questions may be asked to draw up a family tree to estimate the risk of these conditions recurring in your children. Depending on the situation, the geneticist may also order for investigations to be performed to further estimate this risk.

From what you have described, it would suggest that IVF would be the next step if you have failed to conceive despite what has been done so far. At the age of 36, your egg reserves and fertility will start to decline rapidly with each advancing year. Moreover, if and when you get pregnant, you will be at higher risk of miscarriages and the baby will be at higher risk of developing malformations. At the same time, complications in pregnancy such as high blood pressure and diabetes become more common above the age of 35. As you are both healthy currently, I would suggest speaking with your doctor who can advise you on what you should do to optimise your chances of conceiving.

Question by ma18

Dear Dr, I am a 23 year old female. I have been having painful periods for the past few months. I also underwent an ultrasound in July last year and was told that I have a physiological right ovarian cyst, measuring 1.8 x 1.5 x 0.9cm. Will my painful periods or right ovarian cyst affect my chances of being pregnant in the future? Thank you Dr Tan.

Answered by the Department of Obstetric​​s & Gynaecology​​​​:

Dear MA18, 

The ultrasound findings you have described are considered normal findings. Physiological cysts can be described as small fluid collections that develop in the ovary during the process of ovulation (production and release of egg cells). These cysts are temporary findings and would have usually resolved if an ultrasound scan were to be repeated shortly after. Physiological cysts do not typically cause painful periods and do not affect your ability to conceive. Painful periods are a common symptoms that many women do experience. In many women, a definite cause may not be found. 

However, some women with painful periods may have a condition known as endometriosis. This is a condition in which womb-lining tissue is found in abnormal locations, commonly surrounding the ovary. In other cases, the womb-lining tissue may be found affecting the back of the womb, the large intestines and rectum, or occasionally surrounding the bladder. These tissues bleed during the menstrual period, causing irritation and pain. They can also leave behind collections of stale blood leading to “blood-cysts” or “chocolate-cysts”. It is believed that the scarring of the surrounding tissues and the Fallopian tubes can lead to infertility although other theories about how endometriosis causes infertility exist. 

Not all women with endometriosis will have difficulty conceiving though. The ultrasound findings you have described do not suggest endometriosis although it has to be clarified that not all cases of endometriosis may be picked up on ultrasound. I would suggest that if you are worried, you should speak with your doctor. He or she can take a detailed history about your painful periods, perform a physical examination and investigate further.

Question by wario

Hi Dr

Currently i have done my first trimester scanning. And i was detected to have Low PAPP-A-0.426MoM. I would like to check if low PaPP-A will be associated with any high risk pregnancy. As PAPP-A is also associated with down syndrome. Do i need to do Harmony test to re confirm for Trisomy 21.

Answered by the Department of Obstetric​​s & Gynaecology​​​​:

Dear wario,

Pregnancy Associated Plasma Protein A (PAPP-A) is one of the components that is measured in blood tests used in screening for Down Syndrome . The other component is human chorionic gonadotrophin (HCG). These two components are commonly combined with an ultrasound scan of fetal neck thickness between 11-14 weeks’ gestation to screen for the risk of Down Syndrome affecting the fetus (known commonly as either the combined test, First Trimester Screening, or OSCAR test). Apart from Down Syndrome, two other genetic conditions that can affect the fetus (Trisomy 13 and Trisomy 18) are also screened by these tests. Low PAPP-A can be associated with Down Syndrome babies. Low PAPP-A can also predict issues with the placenta leading to pregnancy complications that may restrict fetal growth. As such, the doctor might choose to perform detailed scans at more frequent intervals during the third trimester to make sure that the baby’s growth is unaffected.

It is important to know the results of your first trimester screening, i.e., what is the risk assessment calculation for Down Syndrome (Trisomy 21), Trisomy 13 and Trisomy 18? If these risks were estimated to be less than 1 in 1000, then no further testing for trisomies is usually advised.

Non-invasive prenatal testing (NIPT), one of which is known as the Harmony test, involves obtaining blood from the mother to look for DNA from the baby’s placenta (which is known to circulate in the mother’s bloodstream during pregnancy). NIPT is considered a more accurate test for Down Syndrome compared to FTS. However, it is less accurate for predicting Trisomy 13 and Trisomy 18 compared to FTS. NIPT also does not involve performing an ultrasound scan (compared with FTS). The exclusion of a scan may lead to the possibility of missing other abnormalities in the baby not related to the three trisomies. In addition, NIPT costs the couple significantly more financially compared to FTS although prices have dropped dramatically over the past couple of years.

 As such, NIPT may not be done routinely by all doctors to pregnant women. Instead, it may be offered to mothers who may have an “intermediate” result from FTS (between 1 in 300 to 1 in 1000) or a “high risk” result (greater than 1 in 300). In these women, NIPT may be done as a “second-line” test to further refine the risk estimation before undertaking invasive testing. This refers to the situation where a needle may be passed guided by an ultrasound scan, to obtain amniotic fluid (fluid that surrounds the baby) or placenta cells to rule out an abnormal baby. Invasive testing can potentially cause a miscarriage. NIPT offers the couple a chance to avoid an invasive procedure should the results show “low risk” compared to an “intermediate risk” or “high risk” result obtained with FTS. It is important to note that should the results of NIPT suggest “high risk”, NIPT by itself cannot confirm the diagnosis of Down Syndrome. In these cases, invasive testing would still have to be recommended to confirm the diagnosis.

Question by wario

Hi Dr.

Thanks for the advice. Currently my Trisomy 18 and 13 are 1:14728 and 1:14349 respectively. 

Beside perform detailed scans at more frequent intervals during the third trimester is there any things that i should take note. Like taking more vitamins or calcium pills or etc?

Answered by the Department of Obstetric​​s & Gynaecology​​​​:

Dear wario,

The results you have provided are low risk for Trisomy 13 and Trisomy 18. Based on these results, there is no indication to investigate further. However, you have not indicated the risk calculation for Trisomy 21. It will be important to know what that result is before I can comment further.

As mentioned, a low PAPP-A is associated with placental problems one of which is pre-eclampsia. It will be important to find out more about your history and risk factors. Pregnant mothers who are at higher risk of developing pre-eclampsia may benefit from daily aspirin and/or daily calcium supplementation. I would advise speaking with your doctor to find out more.​

Question by ireneneo

Good day,

I'm currently age 38, a type 2 diabetic taking medications as well as insulin jabs during the night. Besides this, I'm also diagnosed with a growing fibroid near the left side of ovary. With this current situation, is it advisable to start family planning given my age and health issue?


Answered by the Department of Obstetric​​s & Gynaecology​​​​:

Dear Irene,

There are three issues that need to be addressed:

  1. The fertility of a woman declines rapidly after the age of 35. If and when she gets pregnant, she is at higher risk of miscarriages as well as developing complications in pregnancy including baby malformations, high blood pressure and diabetes. Women above the age of 40 are also more likely to experience stillbirths. As you are already 38 years old, it is important to take the above into consideration if you are planning to get pregnant.

  2. Good control of diabetes prior to conceiving is necessary to optimise pregnancy outcomes for women with pre-existing diabetes. In most cases, your doctor may switch you to insulin jabs exclusively (up to 4-5 times a day) once you conceive as insulin has the least likelihood of affecting the unborn baby compared to oral medications. The dose of insulin that you require is also likely to increase as the pregnancy progresses due to the hormonal changes involved. Poor control is associated with miscarriages and fetal malformations especially in the first trimester. In the later trimesters, poor diabetes control can lead to abnormally large babies. 

    Delivery of a large baby can pose potential risks including birth injuries (some permanent) as well as injuries to the mother such as vaginal tears that may extend to involve the “back passage” (rectum). Poor diabetes control is also associated with an increased risk of stillbirth in the late third trimester. Babies born to mothers with poor diabetes control are also at higher risk of developing newborn complications such as breathing difficulties and jaundice.

  3. Uterine fibroids are non-cancerous muscle swellings that can develop in the wombs of up to 30-40 percent of women. The majority of uterine fibroids may not cause symptoms particular if they are small. Fibroids that do not distort the internal shape of the womb are also unlikely to cause issues with fertility. Further information about your “growing fibroid” such as its current size as well as whether it distorts the womb will be required to address your concern. Fibroids can grow when a woman gets pregnant due to pregnancy hormones. It is difficult to predict how these fibroids can affect the ongoing pregnancy. Occasionally, a fibroid may grow so rapidly that it outgrows the ability of the body to supply it with oxygen and nutrients. These fibroids may then degenerate and cause pain. Unfortunately, fibroids that degenerate during pregnancy cannot be removed without affecting the unborn baby. 

    Treatment in such cases would usually involve treating the symptom of pain with painkillers. Surgery to remove fibroids prior to conceiving is not usually recommended unless there is high suspicion that these fibroids are causing infertility. Fibroid surgery during or immediately after childbirth is also not usually advised as there is an increased risk of causing severe bleeding. The majority of fibroids that swell during pregnancy may return to their original size after the body recovers from childbirth. Surgery to remove them may only be advised if they are still significantly large then and/or if they cause symptoms.

I would advise the following:

  1. See your doctor to optimise the control of your diabetes BEFORE you get pregnant in order to reduce complications during pregnancy.
  2. See your doctor to enquire more about the type of fibroid you have and how it may impact your fertility.
  3. Conceive once the above two issues are sorted out due to declining fertility and the issues associated with conceiving at a later age.

Question by mello

Dear Dr,

​I have arrhythmia (extra beats and irregular) for years and have been going to NHC every 6-9 months for review. My husband and I are trying for a baby now and my heart doctor mentioned that mine will be a high risk pregnancy when I get pregnant.

May I know what are the risks/complications? Is there anything I can do to help? I have been taking folic acid, Yun Zhi and Cordyceps.

Thank you in advance for your reply! :)

Answered by the Department of Obstetric​​s & Gynaecology​​​​:

Dear mello,

It depends on what kind of arrhythmia you have been diagnosed with, what symptoms (if any) the arrhythmia might be causing, as well as whether you are on medications to control the arrhythmia.

The blood circulatory system undergoes major changes when a woman becomes pregnant: the overall blood volume increases, the heart rate increases and the heart has to pump and work harder to cope with the demands of pregnancy. It will be important to know how your heart is functioning prior to conceiving. Basic investigations such as an electrocardiogram (ECG) and a ultrasound scan of the heart (echocardiogram) may be performed as a preliminary assessment. Depending on the type of arrhythmia and the symptoms that you may already have or develop later in pregnancy, medications may need to be prescribed. 

These medications may help to reduce the arrhythmia and/or the symptoms that you may experience. If the arrhythmia puts you at higher risk of developing abnormal blood clots within the heart, blood-thinning medications may also be prescribed. In some other cases, a procedure to insert a pacemaker to regulate the heart rhythm may be required. This should ideally be performed prior to conception. The ECG and echocardiogram may be repeated in the late second to early third trimester to assess how the heart is coping with the demands of pregnancy. Depending on the ability of your heart to cope with the demands of labour and childbirth, your doctor will advise you on how you might deliver the baby and what are the precautions that you may need to undertake.

At SGH, we run a monthly specialised pregnancy clinic dedicated to patients with heart conditions in pregnancy. The team consist of obstetricians experienced with high risk pregnancy care, a specialist cardiologist experienced with managing heart conditions in pregnant women, as well as specialised pregnancy-care and cardiology nurses. As you are already a patient of NHC, you may like to speak to your cardiologist. He/she may arrange for an appointment to see us at this joint clinic for advice prior to conceiving, as well as for pregnancy care when you eventually conceive.

Question by simon

Dear doctor,

Need your advice as my wife is carrying a 8weeks baby now. Both of us are thalassemia alpha carrier.

We are worried and heard that there are some test can be carried to define the risk at certain week of pregnancy. Would you advice and details to us on accuracy, test to be done, where can we do such test, risk of those test and the relevant cost of it.


Answered by the Department of Obstetric​​s & Gynaecology​​​​:

Dear simon, 

Thalassemia is an inherited blood disorder in which abnormal genes affect the ability of the body to produce healthy haemoglobin, a blood protein that helps to carry oxygen to body tissues. There are different forms of thalassemia out of which alpha thalassemia and beta thalassemia are commonest in our part of the world. As you have enquired about alpha thalassemia, I will keep my answer focused on this form of thalassemia. 

Healthy haemoglobin is made of four protein chains, two of which are known as alpha chains. Alpha chains are produced by four genes in the body. Mutation or loss of one or more alpha genes results in varying degrees of alpha thalassemia:  

  1. When one gene is mutated, patients rarely develop any symptoms​ 
  2. Individuals with two genes affected may have mild anaemia 
  3. Individuals with three genes affected have haemoglobin-H (HbH) disease. The presentation of HbH disease varies, with some individuals exhibiting mild anaemia, and some others presenting with severe anaemia that may even require frequent and repeated blood transfusion. 
  4. Mutation of all four genes result in the most severe form of alpha thalassemia (alpha thalassemia major). The majority of babies with alpha thalassemia major do not survive beyond birth. 

As carriers of alpha thalassemia, it is likely that each of you have either one or two affected genes of the four involved in the production of alpha chains. A blood test can each be performed for yourself and your wife to determine the genes that are involved. Since you already know that the both of you are carriers, you should ideally have performed this test prior to conceiving. As your wife is already pregnant, I would then advise that you speak to your doctor. He/she may advise for this blood test to be done immediately so that the necessary advice from a geneticist can be given about the probability of your child being affected by the various forms of alpha thalassemia. You may also be referred to the National Thalassemia Registry whose staff will be able to answer your questions about this blood disorder and provide counselling and screening for your families.  

In the event that you and your wife carry gene mutations that may result in your unborn baby being affected by HbH disease or alpha thalassemia major, a prenatal diagnostic test may have to be arranged. This would involve either chorionic villus sampling (a procedure to obtain cells from the placenta for testing) or fetal blood sampling (a procedure to obtain fetal blood from the umbilical cord). The former is performed between 10-12 weeks’ gestation while the latter can be performed at about 18-20 weeks’ gestation. Both tests involve the use of ultrasound to guide the process. As both are invasive tests that carry the risk of miscarriage, I would advise that you speak with your doctor who will provide you with information regarding the necessity for the tests, their risks, as well as the costs involved.