[Hormonal situation on parturition, early puerperium, and lactation (author's transl)]

Variations of the 17-beta oestradiol, progesterone, and prolactin levels in the serum were studied in the context of ten spontaneous parturitions. All cases were investigated within the first five puerperal days, but in five cases additional checks were undertaken over the first four weeks of the puerperium. Milk secretion was measured, as well. The oestradiol and progesterone titres were found to remain below the level common toward the end of pregnancy. They dropped rapidly after parturition and remained low throughout the puerperium. Prolactin underwent slight variation on parturition, but it actually stayed at the high level measurable at full term. Parturition was followed by brief temporary rise and, again, by decline, but values remained above those of non-pregnant women throughout puerperium. Milk production increased gradually over the first five days and remained similarly high throughout several weeks, accompanied by accordingly high prolactin levels. No absolute correlation was found to exist between the extent of lactation and the prolactin level. The presence of a relationship between oestradiol and progesterone levels, on the one hand, and lactation, on the other, cannot be assumed with probability.