Term is technically defined as 37 completed weeks to 42 weeks. The estimated date of delivery is usually calculated at 40 weeks. Pregnancies are not always allowed to get to 42 weeks because of the associated risk of complications.
At this late stage of pregnancy, there is significant weight gain by the baby. The average weight of the baby at term is about 3.4 kg. There is accumulation and deposition of fat underneath the skin and muscles. Most of the lanugo hair would have disappeared from the baby’s skin.
At term, there is complete maturity of the lungs aided by secretion of a hormone called cortisol and a substance called surfactant. Within the intestine, there is a dark green substance called meconium that the baby passes in the first few days of life. When the baby is in danger in the womb, baby may pass this substance into the amniotic fluid and when the membrane is ruptured artificially or spontaneously, this substance called meconium may be seen. Meconium particularly when fresh and sticky could signal an unfavourabe condition for the baby in the womb. Moreso, if there is an abnormality of fetal heart rate recording. This may call for the need for immediate intervention in the form of use of instrument to assist delivery or a ceasarean section
At term, the testes of male babies move to the scrotum and should be felt at birth. The baby receives protection from infections by the build up of antibodies (body soldiers) from the mother.
There is continuous development of the brain and skull of the baby. The skull of the baby at term is not a hard rigid structure but it has allowance in between that allows the skull to overlap over one another and pass easily through the pelvis of the mother.
In most women of Afro-caribean descent, the fetal head does not descend and become engaged until the start of labour, but in women of European origin, engagement of the fetal head can occur as early as 36weeks. The main support for the fetus at term is still provided by the placenta. The placenta at this time weighs about 700g (approximately one fifth the size of the baby). The placenta measures about 24cm in diameter and approximately 2.5cm thick.
The placenta carries the responsibility of facilitating the passage of oxygen and nuitrent to the baby and excretion of waste products from the baby back to the mother’s system.
Warm up contractions earlier described as Braxton Hicks contractions are more. The weight of the pregnant uterus exerts more pressure and back ache is one of the most frequent complain at this stage of the pregnancy. Women also complain of pain over the pelvic bone in front called symphisis pubis. This condition is known as symphisis pubis dysfunction. This is due to excessive relaxation of the ligaments of the pubic bone of the pelvis to allow passage of the fetus.
When excessive strain is placed over the overstretched ligament, it leads to symphysis pubis dysfunction. This condition is characterized by extreme pain and tenderness over this region of the pelvis. In order to reduce symptoms if you are suffering from this condition, avoid straddling movements by keeping you knees together. Avoid swingging your legs apart during movement and change of position. The pain of symphysis pubis dysfunction could be so excruciating that it may be necessary for you to put ice packs over the pelvis for 12minutes every 4hours. In severe forms of pubic symphysis dysfunction, the symphysis pubis bone may separate this is called symphisis pubis diastesis. The pain is quite severe, so bed rest is recommended. The woman with this condition may need elbow crutches to move around
What will happen if I go beyond my estimated day of delivery?
Most women deliver their babies after the estimated day of delivery but before the 42nd week. In many maternity units, pregnancies are not allowed to go beyond 41 weeks and 5 days. This is because of the risk of sudden demise associated with pregnancies that are prolonged. Opinions differ as to further managment of a pregnancy beyond 41 weeks gestation. The first thing to be established is the accurate age of the pregnancy. This can be determined from the last menstrual period and an early ultrasound scan. Ultrasound scan done in late pregnancy are not as accurate. After as certaining the actual age of the pregnancy and you are found to be 40 wks, the protocol adopted by my unit and supported by several randomise control trial is first to “sweep” the membrane around the baby at the top of the cervix. The aim is to stimulate local release of prostaglandin. This procedure of membrane sweeping is not always possible if the cervix is not soft and slightly dilated.
After this procedure one week is given to the woman. She is advised on the symptoms and signs of labour. In the next visit ultrasound scan to determine fetal well being is done. This includes estimation of the quantity of amniotic fluid ,breathing movements of the baby, gross body movements and the ability of the fetus so flex and extend the limbs.A cardiotocographic(CTG) tracing of fetal heart activity is also done All this parameters determined from ultrasound and a CTG machine is known as Biophysical profile(BPP). The ultrasound will also estimate the size of the fetus. A total score of 10 can be obtained. The closer the score is to 10 (ten) the better the state of the fetus. When the fetus is in a fair state it shows that induction of labour can be carried out.With individual risk ad expectation of vaginal deliver, if the score from the biophysical profile is not satisfactory, elective caesarean section is an option.
Another option for a poor score is to cautiously induce labour while continously monitoring the fetal heart with the aid of the cardiotocograph (CTG). The well being of the baby can can be determined more definitely through fetal scalp blood monitoring for acidity A low PH tending towards acidity is a reason for caesarean section. The retional for this second option is that in some instances biophysical profile score is not full proof. At this time of sensitive decision making it is important to cooperate with your doctor because most decisions have to be taken on emergency basis.