Early Pregnancy Changes and Uterine Adaptation

Apuntes

Changes and adaptation to pregnancy They begin in the first week of pregnancy • The uterus-oestrogen stimulate growth and multiplication of myometruim • Grown in size in the first 20 weeks the it elongates • Progesterone-relaxes the myometrium inhibiting contractions and explulsion • Uterine shape-from pear shaped to globular during the first 12 weeks • Position-in pelvic before pregnancy,at pelvic brim at 12 weeks, at 16 weeks it has grown half way between symphysis pubis and umbilicus, at 24 weeks it is 1 cm above the umbilicus. at 30 weeks midway between umbilicus and xiphi sternum, at 36- 40 weeks at level of xiphi sternum. • At 36-38 weeks in primigravida fetal head may angage into the pelvic cavity • The corpus luteum produces progesterone and oestrogen • These hormones make the decidua mostly the fundus thicker ,richer and more • The fundus is the probable site for implantation • This provides an environment which is rich in glycogen for the blastocyst until the • The corpus luteum is maintained by the human chorionic gonadotrophin hormone till • Once the placenta is fully developed the HCG no longer maintains the corpus luteum • The placenta takes over production of hormone...