CHAPTER 5 NORMAL PUERPERIUM
SECTION 1: CHANGES IN MATERNAL PUERPERAL PERIOD
From the time of delivery of the placenta the maternal body along with the different organs except the breast return to normal or near normal nonpregnant state over a period of time. This six week period is called the puerperium. The recovery of cardiovascular and psychological functions may take several months.
1. Changes in the reproductive system
1.1 The uterus: The changes of uterus are the greatest. After delivery of fetus, the process of the uterus gradually returning to the non pregnant state is called uterine involution. The main changes are reduction in uterine muscle fiber size and endometrial regeneration. A week after the birth, the uterus shrinks to about 12 weeks size of gestation, and can be palpable just above the pubic symphysis. Ten days after the birth, the uterus reduces into the pelvis. Six weeks after birth, the uterus returned to the non pregnant size. Postpartum endometrial regenerates and form a new functional layer. In addition to the placental attachment site, the surface of the uterine cavity is replaced by the new endometrium. The repair of placental-en-dometrium need to 6 weeks. During delivery the cervix is lacerated at the 3 “o” clock and 9 “o” clock position. The cervical opening contracts, thickens and the external os retracts but does not completely resume its pregravid appearance. It is wider, with depressions at the 3 and 9 “o” clock positions. This is called the parous cervix.
1.2 The vagina: The vulva, vaginal wall muscle tension is restored gradually. The vaginal cavity shrinks. Minor perineal lacerations and lateral incision sutures heal days after delivery.
1.3 The pelvic tissue: The pelvic floor muscles may be re-stored to a state close to the non pregnant state in puerperium. Tissue edema disappeared within a week after delivery. Severe tear of the pelvic floor muscle and fascia will lead to the relaxation of the pelvic floor. Early resumption of heavy physical labor will cause vaginal wall prolapse, even uterine prolapse.
2. The breast changes
The main change of the breast is to facilitate lactation. Sucking is the key link to keep lactation going continuously. The continuous emptying of the breast is an important stimulus to maintain the secretion of breast. The secretion of breast is closely related to the nutrition, sleep, moods and health status of the puerpera. It is vital to ensure maternal rest, enough sleep, delicious nutrition rich diet, and avoid mental stimulation.
After placental expulsion, parturients feed the baby with their own milk. Colostrum is the secretion of the breast for the 24-48 hours after delivery, beta-carotene gives it pale yellow. This thin fluid containsfat globules, acinar cells and colostrum corpuscles, proteins, variety of antibodies, especially lgA. Colostrum gradually changed into a mature white milk in the next 4 weeks.
3. The changes of the circulatory system and blood system
After delivery of the placenta, a lot of blood from the uterus enters the systemic circulation. Along with interstitial fluid reabsorption, the blood volume increased by 15%-25% within 72 hours after delivery. The puerpera who had a history of heart disease is prone to develop heart failure. Blood volume gets restored to the non-pregnant state 2-3 weeks after delivery. Blood is in a hypercoagulable state in early puerperium. This is beneficial to the formation of thrombus in the placenta, and reduction of postpartum bleeding.
4. The changes of the digestive system
The muscular tension of the stomach and small intestine decreases, and the peristalsis weaken. It will restore two weeks later. Lying in bed for a long time, lack of exercise, lumbar muscle and pelvic floor muscle relaxation, can all cause constipation.
5. The changes of the urinary system
Excess water retention is now secreted by the kidneys. Hence urinary output increases in the first week of postpartum.
Bladder pressure induced mucosal edema and congestion, decrease muscle resulting diminished bladder sensitivity along with perineal wound pain leads to urinary retention.
6. The changes of the endocrine system
Menses and ovulation time are influenced by Breastfeeding.
In breast-feeding mothers menstruation returns 4-10 weeks postpartum. Ovulation usually occurs 10 weeks postpartum. In breastfeeding women, ovulation is postponed by 4 to 6 months postpartum. It is also possible that ovulation can occur before menstruation. So in breastfeeding puerperae pregnancy can occur before menstruation occurs.
7. The changes of the abdominal wall
During pregnancy, the lower abdominal midline appears pigmentation, the linea nigra. This gradually subsides once the puerperium is over. Striae gravidarum: These are slightly depressed linear marks of varying lengths and breadth found in pregnancy. Imnitially, they are pinkish before delivery. But after delivery they become glistening white, and are called striae albicans. Abdominal tension recovers within 6-8 weeks post-partum.
（刘琼 李华）