Multiple deliveries is one that comprises of the birth of more than one baby. It could be twins, triplets, quadruplets and so on, even in most rare cases, octuplets. Multiple births are extremely rare in large mammals, with the exception of humans.
Multiple pregnancies occur as a result of fertilisation of an egg, which splits into two or more to give rise to a foetus who turns out to be identical, or as a result of fertilisation of two or more eggs, turns out to be fraternal. Sometimes, it is a combination of both factors. A pregnancy that results in a single cell is known as monozygotic, from two zygotes is known as dizygotic, from three or more zygotes is known as polyzygotic.
The average gestation period for a single pregnancy is 38 weeks (approx. 9 months). This reduces with the increase in number of foetus. It reduces to 36 weeks for twins, 32 weeks for triplets and about 30 weeks for quadruplets. With the decrease in the gestation period, there is a subsequent increase in risk associated during and after birth.
Multiple births can different forms like;
This is the most common form of multiple births in humans, with about 1 in 30 births each year. Twins can be fraternal or identical, based on several factors. If one egg is fertilised and ends up splitting into two, the resulting foetuses are identical twins. In another case, where two eggs are fertilised, it gives rise to fraternal twins. Contrary to popular belief, identical twins do not run in families. This means that every family has an equal chance of having identical twins. However fraternal twins can run in families.
The hyperovulation gene responsible for influencing twins can only be used by the mother, and thus, the father cannot influence the birth of twins in his family even if he comes from a family of twins or is one himself. He can however pass it down to his daughter.
Triplets are less common than twins, with about 1 in 1000 births. They can be identical or fraternal or both. Triplets are identical when one fertilised egg splits into two, and one part splits further again. This is very rare and does not happen often. Also, they could be as a result of three different eggs being fertilised, or a combination of both, whatever two eggs are fertilised and one egg splits into two. The odds of having identical triplets are extremely rare.
3. Quadruplets and more
There have been reports of people who have had more than three babies at once. Although they are less common than triplets. Quadruplets, which is having four babies at once is becoming increasingly common due to fertility treatments. Quadruplets can be identical or fraternal or a combination of both. There have been other reports of quintuplets, sextuplets and very rarely septuplets, octuplets and nonuplets. The problem does not lie in having more than two or three babies; the problem lies in them surviving birth and infanthood. Very few cases of such multiple births have been recorded to have survived infancy.
Causes of multiple births
Some issues have been accepted as being some influencing factors of multiple births. Notwithstanding, multiple births can occur naturally without some outward factors.
Furthermore, multiple births can be influenced by;
For some reasons not yet known, it is believed that the older a woman gets, the more likely she is to have multiple births naturally. This is believed to be as a result of a higher level of follicle stimulating hormone that older women seem to have. Women over 35 are more likely to have multiples than younger women.
The use of fertility drugs increasingly increases one’s chances of having multiples. This has been verified by results, data information and observations.
Risks associated with multiple births
1. Premature birth
Multiple pregnancies often do not get to full term. The higher the number of foetuses, the higher the risk of premature birth. Also, up for consideration is the fact that multiples tend to have low birth weight as compared to single babies.
There are high mortality rates in multiples than single births. It is more common for one or more or all babies in multiple births to die than it is for a single birth. This does not mean that it is not possible for all of the babies in a multiple birth to survive, it just means that it’s more likely for there to be stillbirths in multiples than singles.
3. Incomplete separation
Multiples may end up sharing amniotic sacred, resulting in the risk of nuchal cord or umbilical cord compression. In more serious cases, there could be an incomplete separation of eggs, resulting in conjoined twins or babies.
Issues to consider during multiple pregnancy and delivery
1. Pregnancy care
Women having multiple babies should see their doctors and midwives more often than single pregnancies because of the higher risk of complications.
A high – calorie diet is strongly recommended for multiples for an increase in birth weight.
3. A vaginal delivery or Caesarean section ( CS)
The fetal position of the babies determines the birth method. The state of health of the mother should also be considered. CS can be adopted if there are complications.
4. Neonatal intensive care
Immediately after being born, multiples are usually admitted into neonatal intensive care to monitor for any possible complications.