Hormones 2016

Male pregnancy
root), preventing the necessary nourishment for the hair getting through
for proper growth. DHT causes the hair follicles to shrink. The growing
"anagen" stage of the hair is shortened and the resting "telogen" stage is
extended. Eventually these hairs stop growing.
Androgenetic alopecia (AGA; male-pattern baldness) is a hereditary and
androgen-dependent progressive thinning of the scalp hair that follows
a defined pattern (Stanczyk, 2006). While the genetic involvement is
pronounced but poorly understood, major advances have been achieved
in understanding the principal elements of androgen metabolism that are
involved. DHT may be related to baldness. High concentrations of 5
alpha-reductase have been found in frontal scalp and genital skin and
androgen-dependent processes are predominantly due to the binding of
DHT to the androgen receptor (AR). Since the clinical success of treatment
of AGA with modulators of androgen metabolism or hair growth promoters
is limited, sustained microscopic follicular inflammation with connective
tissue remodeling, eventually resulting in permanent hair loss, is considered
a possible cofactor in the complex etiology of AGA (mayomedical, 2016).
Male pregnancy
Male pregnancy is the carrying of one or more embryos or foetuses
by the male of any species inside their bodies. The majority of all
pregnancies in the animal kingdom are carried by female organisms. In
most heterogamous species 135 , the males produce the spermatazoa 136 and
rarely host the zygote 137 .
Speculation on inducing pregnancy in men
British physician Robert Winston speculates that it may be possible to
surgically induce abdominal ectopic pregnancy in men (unknown, 1999). In
his book "The IVF Revolution", Winston speculates that an embryo could
be implanted in a man’s abdomen – with the placenta attached to an internal
organ such as the bowel – and that the baby would later be delivered by
Caesarean section. However, other experts expressed great concerns about
the safety of such a procedure.
135 In reproductive biology, heterogamy or heterogamous is often used as a synonym of
heterogametic, meaning the presence of two unlike chromosomes in a sex. For example,
XY males and ZW females are called the heterogamous sex
136 one of the minute, usually actively motile gametes in semen, which serve to fertilize
the ovum; a mature male reproductive cell
137 the cell produced by the union of two gametes, before it undergoes cleavage
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