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Register for The Relationship Between Placental Location and Fetal Gender
(Ramzi’s Method):
Can Placental / Chorionic villi Location be used as Indicator for Fetal Gender
at Six Weeks Gestation using 2-D and Color Flow Sonography?
ORIGINAL RESEARCH
By
Dr. SAAD RAMZI ISMAIL
Ultrasound Supervisor / Instructor
NWHC-High Level Hospital-Alberta
Pobox-1462, High Level, Alberta, T0H1Z0
Canada
DECEMBER 2007
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Uterine Contraction
Uterine contraction begins asymmetrically a “pacemaker” in one uterine horn, and
that progesterone from the placenta blocks myometrium contractibility primarily at
the site of implantation. Case records were examined at 182 patients who had
placental locations performed and who had a spontaneous onset of labour Where
the placenta was implanted in the right upper quadrant of the uterus labour
occurred on average four days sooner than when it was implanted in the left
upper quadrant” the difference was statistically significant 43.
This theory also mentioned by Larks work on the human electrohysterogram. Larks
proved that electricity create contraction or expansion of the uterine muscles
on his study of 293 subjects in labour using ECG –bipolar electrodes 44.
Monitoring of uterine contraction activity is an important diagnostic tool used
during both pregnancy and labour. The strain the pregnant uterus exerts on the
maternal abdomen is measured via external tocography 45. However, limitation of
this approach has caused the development of another technique-electohysterography
- that is based on the recording of electrical uterine activity. The comparison
study between electrohysterography and tocography was carried out thanks to the
possibility of simultaneous recording of mechanical and electrical uterine
activities 44, 45.
Endometrial wave like movements have been characterized and found to be of
relevance to fecund ability during the natural ovarian cycle 46, 47, 70.
Researchers found evidence that a greater frequency of contractions on the day
of embryo transfer appears to be associated with a reduced pregnant rate but
others observed the converse 46, 47, 48. To describe endometrial contractility,
the term junctional zone contraction is used because there is evidence that this
particular layer of myometrium, which consists of a discrete compartment of more
compacted myocytes, may be responsible for the wavelike movements of the
adjacent endometrial 49, 50.
Polarity and Cellular Communication
The polarity cycle which unknown to most of us was there in addition to the ovulation/menstrual cycle .When the ovum membrane is neutral; sperms carrying either the X or Y chromosome can unite with the ovum and fertilize it 51. During this period, the chances of getting a baby boy or baby girl are 50: 50. When the ovum, membrane is positively charged, it attracts the sperm carrying X chromosome (which is negatively charged) and a baby girl is produced. Scientist researching cellular communications has found that the mother’s ovum membrane’s receptors had an alternating polarity (energy) that accepts or rejects the “x” or “y” chromosome sperm according to her energy cycle 51, 52.
Researchers found that the “y” chromosome sperm had a constant different charge to “x” chromosome sperm 51, 52. French scientists went further and verified that the ovum membrane receptors produce a different and alternating polarity that occurred as a result of a mother’s biological clock that they call the polarity cycle 51, 52, 53. The ovum membrane’s alternating polarity is nature’s way of selecting sperm with different gender determining chromosomes52, 53.
Genes, Hormones and Sex Determination
Researchers know at present that gender determination in man has a genetic origin, but there are other mechanisms that apply in some animals. It appears, for instance that sex may be determined by the incubation temperature of the eggs, which can modify the action of enzymes such as aromatase. Elsewhere, similar systems may have evolved separately and are found in widely divergent species 54, 55, 56. This is called concerted evolution.
Databases searches seeking similar sequences in humans have found a human cDNA that encodes a protein with a DM domain. Moreover, the expression of this protein is seen only in the testis. It is been called DMT1 (DM-Testis) 54, 55, 56.
Moreover, this gene appears to be critical in human sex determination, since
mutations in this region is associated with male to female sex reversal. DMT-1
related sequences have also been found in the chick of alligator, and mouse. The
DMT genes are expressed only in the genital ridges of male embryos. This
suggests that male sex determination using a common gene in sex determining
mechanisms in both vertebrates and invertebrates 54, 55, 56.
Sex hormones influence the biological activities throughout our lives, beginning
with signaling for certain fetal tissues to differentiate into structures that
are specific for male or female 57.
Dr Gellersen (1994), study showed that the regulation and function of a newly discovered mammalian polypeptide hormone, stanniocalcin (STC). SCT was originally described as a potent calcium-lowering hormone in fish and has only recently been discovered in mammals and their studies have shown mammalian STC is most highly expressed in the ovary 58.
Male and Female Sperms
Scientists can now identify the male sperm (i.e. carrying Y chromosome) from female sperm (i.e. carrying X chromosome) by means of fluorescent material that attaches itself to the Y chromosome only under the ultraviolet light; the Y carrying sperms fluoresce and glow. According to Hamilton and Mossman (1992), the sex of aborted fetus at six weeks cannot be determined by histological examination of the gonads 59.
Sex Chromosomes
Sex not always determined by sex chromosomes but sometimes by environmental triggers 60, 61. The nuclei of human cells contain 22 autosomes and 2 sex chromosomes. In females, the sex chromosomes are the 2X chromosomes. Males have one X chromosome and one Y chromosome. The presence of the Y chromosome is decisive for unleashing the developmental program that leads to a baby boy 60, 61, 62. Today the X chromosome is still home to thousands of genes, but the Y chromosome has only a few dozen. Of those, 19 are shared between the X and Y 60, 61, 63, 64. These 19 genes are essentially living fossils in that they are able to provide scientist with information about the sex chromosomes and their evolutionary history as well 60-64.
Implantation
When the embryo reaches the uterus it must hatch from the zona pellucida in order to implant. The zone pellucida keeps the embryo from implanting in the walls of the oviduct. When this happens it is called a tubal pregnancy or an ectopic pregnancy and can be very dangerous for the mother. When free of the zona pellucida, the blastocyst can make direct contact with the lining of the uterus (Figures 24, 25) 65, 66. The next major step in human development is called gastrulation. This is the point at which the cells of the embryo form three tissue layers, the endoderm (inside layer), mesoderm, and ectoderm (outside layer). This is one of the most crucial points in development where a great deal of differentiation occurs 67. Maternal effects are broadly defined as the impact that the mother and her phenotype have on the phenotype of the offspring 61, 68. This is quite distinct from the genetic effects that a mother has on her offspring’s phenotype.
Pyelectasis
Fetal Pyelectasis is a pelvicaliceal dilatation. It can be classified according
to the gestational age (Figures
19,
20) 71.
Between 15 and 20 weeks: greater or equal to 4mm.
Between 20 and 30 weeks: greater or equal to 5mm.
Between 30 and 40 weeks: greater or equal to 7 mm.
Persistent fetal pyelectasis is defined as greater than 7mm in the third
trimester 71.
Urinary tract abnormalities can be found in up to 5% of newborns; they account
for 25% of congenital defects, and contribute to 4% of the prenatal mortality
72. Pyelectasis is usually bilateral (57%), and it is more common in the left
kidney 73. Male fetus exhibit a significantly increased frequency of renal
pelvic dilatation compared with female fetus at 3/1 ratio 74.
Diagnosis is made by sonographic measurement of the renal pelvic anteroposterior
diameter 75.
Mild pyelectasis is a common finding, with no significant long term effect (Figure 20). However, there is a small association with aneuploidies, especially trisomy 21. The incidence of Down syndrome is 3.3% when pyelectasis are found, and 25% of fetuses with trisomy 21 have pyelectasis 76. The risk of chromosomal anomalies increases when the pyelectasis diagnosed in older women over 35 years of age or if it is associated with other sonographic soft markers 77.
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