From why twins could in fact be half-brothers or half-sisters, to why you need to monitor your baby’s movements … here are 10 facts about pregnancy you need to know!
1 Many women spend most of their adult lives trying not to get pregnant, but it is actually only possible to conceive on approximately 2–3 days of the month during ovulation. Sperm can survive in the female reproductive system for up to 3 days in their quest to fertilise an egg.
2 For some women, it could be possible to be pregnant with two babies from different fathers at the same time. It is rare but this can happen if, during ovulation, two eggs are produced at different times usually within the same ovulation cycle and both are fertilised. This could result in twins which are actually half-brothers or half-sisters!
3 As a species, we have evolved to aid in the delivery of babies by giving birth when the baby is immature. If a baby weighs approximately 3300g at birth, their brain may weigh around 335g. A great deal of brain development occurs after the birth where the brain increases in size to weigh approximately 1000g by 20 months of age.
4 In pregnancy, your total blood volume can increase between 30–50% (and even more in the case of a twin pregnancy). There is a greater increase in plasma (the liquid portion of your blood) than red cells, and this is why in the middle of pregnancy, your haemoglobin can fall, leading to anaemia. However, this increase in blood volume aids circulation, increases blood pressure when blood is directed to the lower part of the body in the latter part of pregnancy, and also helps the placenta to be perfused with blood. Lastly, the extra blood volume provides a safety buffer from losing too much blood in childbirth through haemorrhage.
5 During pregnancy, you are more at risk of developing diabetes due to the effects of hormones on insulin. Insulin is the key which allows the energy from our food into our cells but, during pregnancy, the body is less sensitive to insulin and less insulin is produced.
6 In days gone by, women used to be advised that during pregnancy they should be eating for two and this caused some women to gain a lot of unnecessary weight. In reality, the extra calories you may require during pregnancy could be achieved by eating an apple and a small pottle of yoghurt per day. Some women who currently have a high body mass index (BMI) may be recommended by their midwife to monitor their weight gain in the pregnancy and aim to put on a smaller amount of weight than a woman of a normal BMI. Breastfeeding is actually the time when women of normal BMI may need to take on more calories, as breastfeeding can expend up to 600 calories per day.
7 Hormones in pregnancy such as progesterone and relaxin can cause ligaments and joints to soften and relax. Pregnant women who are exercising should take care to avoid strenuous or unusual activities which could cause injury due to the suppleness of joints. In childbirth however, these hormones can help to create more room for the baby to be born by allowing the coccyx in the pelvis to move backwards. This happens more easily if the woman is in an upright position as it allows more room for the coccyx to move.
8 Mums-to-be can provide the most important information on their
baby’s wellbeing while in utero. Monitoring fetal movements and especially recognising changes to normal patterns of movement for their baby is extremely important. Any woman concerned about decreased fetal movements should not hesitate to contact their midwife immediately, rather than wait for the next antenatal appointment.
9 Women often confuse when actual labour starts and begin timing their labour from the very first contraction or tightening. In reality, many women can first go through a latent stage of labour, which involves irregular tightenings and contractions that vary in length, strength and frequency. These contractions are not part of the active stage of labour but are a precursor. A lot of work has to be done to the cervix in addition to the actual dilatation (opening), such as shortening and thinning which can happen during the latent phase. You are in established labour when you are having regular, painful contractions, increasing in strength and lasting for approximately 60 seconds.
10 For women to labour effectively, they need to be in an environment where they feel safe and with people that they trust. Often labour can slow down when a woman first goes to hospital. Think of labour hormones as being shy – they work best when a woman does not feel stressed, but feels as comfortable and as relaxed as possible. A dimly lit room with relaxing music and comforts from home is ideal.
Lara Sexton is a registered hospital midwife, and mum of two lovely girls, who lives in Auckland.