Pregnancy with multiples
This article will focus on twin pregnancy as this is the most common type of multiple pregnancy.
Generally, twin births would naturally occur in around 1 in 100 pregnancies, but the number of twins born is rising due to various treatments now used for infertility. Triplets are extremely rare naturally - with an incidence of around 1 in 8000 pregnancies, although they too have increased since advances have been made in fertility technology. Quads or quints are rarer still.
Many factors influence the conception of multiples such as age, genetics, medications and ethnicity. If you’re expecting more than one baby you will have different health needs and may require extra practical support and understanding throughout pregnancy and the postnatal period. This article will focus on twin pregnancy as this is the most common type of multiple pregnancy.
Types of twin pregnancy
Twins will be either identical or non-identical (fraternal) twins. Identical twins develop from a single egg splitting after fertilisation and these twins will be of the same sex and have the same genes, blood group and physical features. They may however be different sizes and often have very different personalities. Fraternal twins develop from two eggs that have both been fertilised by two sperm and are no more alike than any other brother or sister. They can also be different sexes.
There are several different ways that twins can develop in the uterus. Identical twins can either share a single placenta, chorion (the outermost membrane of the sac) or amnion (the innermost membrane of the sac), or share a single placenta and have one chorion with two amnions.
Identical or fraternal twins can have two separate placentas, chorions, and amnions, or have a fused placenta with two chorions and amnions. This is important to know because twins can still be identical even if they are in their own sacs and with their own placentas. The information about their sacs and placentas can also be important when considering any associated risk factors with having twins. Knowing if your twins are identical or fraternal will either be established during pregnancy or soon after birth.
Signs of twin pregnancy
Signs of twin pregnancy can include in many (but not all) cases some of the following:
- Excessive morning sickness (nausea, vomiting)
- Extreme fatigue (stress, poor nutrition, work, other children will also influence energy levels)
- Sleepiness and lethargy (your body is working even harder to nurture two babies)
- Elevated hCG levels (but not in all cases)
- Abnormally high Alphfetoprotein (AFP) test
- Measuring large for your pregnancy stage
- Early/frequent foetal movement
- Increased weight gain
- Detection of two babies upon feeling your tummy
- Detection of two heartbeats
A family history of twins will also be an important factor, as will your own intuition! You may just feel it!
Confirming a twin pregnancy
Usually a twin pregnancy will be confirmed with an ultrasound scan and can often be confirmed as early as six weeks into your pregnancy.
Twins sharing a chorion will usually be scanned every two weeks to check their growth. Twins with two chorions would generally be scanned at 20 weeks (as with a single pregnancy) and then usually every four weeks thereafter.
Twin pregnancy
Being pregnant with twins tends on the whole to be shorter than a single pregnancy. The average time for twins is 37 weeks rather than 40 weeks. However, mums carrying twins however are still given an estimated due date at 40 weeks, but should know the likelihood of having their babies earlier is higher.
If you are pregnant with two babies, your hormone levels will be higher, which can, unfortunately, increase the common problems of pregnancy.
Back and joint discomfort are common are common with twins because of the level of circulating hormones that relax your smooth muscle, as well as the additional weight gained and stretching of the abdominal area. A physiotherapist can help with postural advice, exercises, and provide supportive belts. Your doctor or midwife can refer you if required.
Having twins also makes greater demands on your iron stores, so iron levels should be monitored throughout pregnancy by your doctor or midwife during routine antenatal checks.
With a twin pregnancy there can also be an increase in various complications of pregnancy which should be discussed with your health care professional as soon as it’s confirmed you are carrying twins. This information will help you and your doctor or midwife tailor a care plan for your pregnancy and birth that suits your individual needs.
The news of expecting twins may come as a considerable surprise for some couples, so it is important to discuss any of your worries or concerns with your doctor or midwife who can offer you additional information, support and links to associations that are specifically geared to support multiple babies and parenthood.
Preparing to breastfeed twins
It is also important to think about how you will feed your twins - both from a nutritional and practical perspective! It is entirely possible to breast feed twins, and breast milk is certainly the best nutrition for babies.
The advantages for breastfeeding twins are the same as for single babies, but because twins have a higher tendency to be born prematurely and small for their age, it is even more important for their health that they receive breast milk.
There are countless sets of twins who have been exclusively breastfed and others who are fed with a mix of breast milk and formula. There are also many organisations that can help you prepare during pregnancy for breastfeeding twins. See our support services section under breastfeeding support for details.
Your doctor or midwife will be able to discuss the benefits of breastfeeding with you, and provide you with information on classes and support services in your area. Talking with other mothers who have successfully breastfed their twins is also a great opportunity for encouragement and reassurance. Our forums are also a good place to chat with other families with twins.