1.1 Introduction
The menstrual cycle is the cycle of natural changes that occurs in the uterus and ovary as an essential part of making sexual reproduction possible (Lentzet al., 2012). Its timing is governed by endogenous (internal) biological cycles. The menstrual cycle is essential for the production of eggs, and for the preparation of the uterus for pregnancy (Lentz et al., 2012). The cycle occurs only in fertile female humans and other female primates. In human females, the menstrual cycle occurs repeatedly between the ages of menarch, when cycling begins, until menopause, when it ends.
As a prelude to other parts of this study, this chapter will discuss the background upon which this study was initiated, the statement of problems that led to this study, the Aim and Objectives of the study. Others are Significance of the study, Scope of work, Research questions, Limitation of the study and Definition of technical terms.
1.2 Background of Study
Over the years, the length of a menstrual cycle in humans varies greatly among women (ranging from 21 to 35 days), with 28 days designated as the average length. Each cycle can be divided into three phases based on events in the ovary (ovarian cycle) or in the uterus (uterine cycle) (Anderson et al., 2003). The ovarian cycle consists of the follicular phase, ovulation and luteal phase whereas the uterine cycle is divided into menstruation, proliferative phase, and secretory phase. Both cycles are controlled by the endocrine system and the normal hormonal changes that occur can be interfered with using hormonal contraception to prevent reproduction (Klumpetet al., 2013).
By convention, the length of an individual menstrual cycle in days is counted starting with the first day of menstrual bleeding. Stimulated by gradually increasing amounts of estrogen in the follicular phase, discharges of blood (menses) slow then stop, and the lining of the uterus thickens. Follicles in the ovary begin developing under the influence of a complex interplay of hormones, and after several days one or occasionally two become dominant (non-dominant follicles atrophy and die). Approximately mid-cycle, 24—36 hours after the Luteinizing Hormone(LH) surges, the dominant follicle releases an ovum or egg in an event called ovulation.
After ovulation, the egg only lives for 24 hours or less without fertilization while the remains of the dominant follicle in the ovary become a corpus luteum; this body has a primary function of producing large amounts of progesterone. Under the influence of progesterone, the endometrium (uterine lining) changes to prepare for potential implantation of an embryo to establish a pregnancy. If implantation does not occur within approximately two weeks, the corpus luteum will involute, causing sharp drops in levels of both progesterone and estrogen. The hormone drop causes the uterus to shed its lining and egg in a process termed menstruation (Klumpet et al., 2013).
The menstrual cycle is characterized by cyclical fluctuations in the levels of FSH, LH, estrogen and progesterone The hormones are known to have an effect on oxygen carrying capacity, immune response, bleeding and also changes in serum electrolyte which may be responsible for variable physical, psychological symptoms and autonomic changes. It is suggested that stressful situations during ovulatory periods and menstruation may cause increased 17-hydroxy corticosterone levels with resulting eosinopenia (Feuring M et al., 2002). Platelet function is periodically altered during the ovarian cycle due to the influence of progesterone and estrogen on Von Willebrand factor concentrations (Sioban et al., 2004). Ovarian hormones influence almost all the systems of the body.
They are known to alter the immune system like depression of the suppressor T cell activity Human & animal studies suggest that there is a change in the distribution of immune cells during different phases of menstrual cycle (Pehlivanogluet al., 2001). 5—20% of women reporting severe dysmenorrhea (painful menstruation) which may be associated with reproductive morbidities like infection (Sioba´net al., 2004), thus estimation of leucocyte count is an important tool. Females have more asthma throughout the reproductive years. Female sex steroids are pro-inflammatory and will increase the susceptibility to atopy (Sioba´net al., 2004).
In developing countries, abnormal uterine bleeding appears to affect about 5—15% of women of reproductive age. It is a major cause of gynecological morbidity, affecting up to one in five women some point during their reproductive life span Reproductive-aged women of about 9-14% have blood loss that exceeds 80 ml (Rajneeet al., 2010) and prolonged and excessive bleeding may provoke or exacerbate anaemia and in a certain percentage of cases, may eventually be life threatening if left untreated, thus there arises a need to estimate Haemoglobin, Red Blood Cell count and ESR during the menstrual cycle. The lack of awareness about the potential importance of reducing menstrual flow when women are anaemic and lack of knowledge among women about treatment alternatives is of some concern. The maintenance of different blood corpuscles at normal levels during the menstrual cycle is necessary. Therefore, in the present study, haematological modulation in the different phases of menstrual cycle was studied (Silverthornet al., 2013 and Sherwood et al., 2013).
Therefore, in Nigeria where the research was carried out, the activities that was conducted is to comparatively analyze the uterine menstrual cycle and the hematological indices of students in the University of Benin.
1.3 Statement of Problems
Investigation revealed that in developing countries, abnormal uterine bleeding appears to affect about 5–15% of women of reproductive age. It is a major cause of gynecological morbidity, affecting up to one in five women some point during their reproductive life span Reproductive-aged women of about 9-14% have blood loss that exceeds 80 ml (Rajneeet al., 2010) and prolonged and excessive bleeding may provoke or exacerbate anaemia and in a certain percentage of cases, may eventually be life threatening if left untreated, thus there arises a need to estimate Haemoglobin, Red Blood Cell count and ESR during the menstrual cycle.
The lack of awareness about the potential importance of reducing menstrual flow when women are anaemic and lack of knowledge among women about treatment alternatives is of some concern. The maintenance of different blood corpuscles at normal levels during the menstrual cycle is necessary. Therefore, in the present study, haematological modulation in the different phases of menstrual cycle was studied (Silverthorn et al., 2013 and Sherwood et al., 2013).
1.4 Aim and Objectives of Study
The aim of the study is to comparatively analyze the uterine menstrual cycle and the hematological indices of students in the University of Benin. In achieving this aim, the following specific objectives were laid out as follows:
To compare the Hematological parameters during different phases of menstrual cycle among female students in the study area;
To compare the Differential leucocyte count during different phases of menstrual cycle among female students; and
To compare the Serum electrolyte levels during different phases of menstrual cycle among female students in the area under review.
1.5 Research Questions
The study came up with research questions so as to be able to ascertain the above stated objectives. The specific research questions for the study are stated below as follows:
Are there red cell and the white blood cell indices in uterine menstrual cycle of students in the area under review?
What are the hematological values of the ovulation phase with the luteal phase of the menstrual cycle?
1.6 Significance of Study
This research will be of benefit to the female gender. This study will help in detecting disorders in the menstrual cycle of a woman. These disorders can be easily detected by the reduction of blood flow or the increase in the duration of flow (number of days).
Menstrual disorders like delayed or early menarche, premenstrual symptoms and dysmenorrhoea create a great anxiety among adolescent girls and their families, thus it is of enormous significant to know the age at menarche for girls‘ clinical evaluation, education and identification of deviations from normal.
Investigating the age of menarche and menstrual problems among adolescent is also important so as to provide health planners and caregivers with fundamental data necessary for interventions.
The 6 knowledge of age at menarche in a given population is a pressing need of the society as no law about the age at marriage, consensual sex, abortion, family planning, rape and other aspects of female reproductive life can be made without it. With emergence of acquired immune deficiency syndrome as one of major threat to mankind and teenage pregnancies as one of the major social problems, an urgent need is felt, in developed as well as developing countries to make the adolescents aware of it.
This study will be of immense benefit to other researchers who intend to know more on this study and can also be used by non-researchers to build more on their research work. This study contributes to knowledge and could serve as a guide for other study.
1.7 Scope of Study
The scope of the research is focused on the Comparative Analysis of the Uterine Menstrual Cycle and the Hematological Indices of Students in the University of Benin.
1.8 Limitations of the Study
During the course of this study, many things militated against its completion, some of which are:
Time Constraint: The time frame given to accomplish this project was very short due to school academic calendar and it was carried out under pressure which made the researcher not to implement some necessary features.
Research material: availability of research material is a major setback to the scope of the study.
Frequent power failure: This made the researcher append more money on fuel to ensure sustainable power.
Financial Constraint: Insufficient fund tends to impede the efficiency of the researcher in sourcing for the relevant materials, literature or information and in the process of data collection (internet).
